As the development of high performance and multiple functions for mobile electronic devices like cellular phones, personal digital assistants (PDAs) and laptop computers continues, the combination of digital image acquisition technology with mobile electronic devices has become an important trend in the development of mobile multimedia technology.
In recent years, miniature lens modules for image acquisition for use in such mobile devices have been gradually upgraded from traditional fixed-focus lenses to zoom lens systems. A typical zoom lens module uses a voice coil motor (VCM) or stepping motor and a mechanical driving system to drive a lens module mounted in a lens barrel to allow zooming/widening (depending on direction driven). However, the mechanical structure of such a zoom lens module tends to be relatively complicated and bulky. The assembly typically requires a large number of components to perform the selectable zoom function by facilitating the driving of the lens module mounted in the lens barrel. As a result, it has proven difficult to reduce the size and volume of the zoom lens module. Meanwhile, as the mobile devices become lighter, thinner and smaller, the typical zoom lens is difficult to incorporate into mobile devices, and the production cost thereof is high.
Therefore, it is desirable to provide a zoom lens module of simple structure and smaller volume.